Will Changing my 100 Watt Tube Amp to a 200 Watt SS Amp Solve My Problem?

Mark, your ARC LS25 is a  selectable gain line stage. It looks like you can set the gain anywhere between 0 dB and 18 dB. What do you currently have the LS25 gain set at?

Cheers,
John

John, I have it set to 18db. I was told that setting is the native setting, and the lower gain settings were attenuated.

matt, I have toyed with this idea. If I were to sell my amp and preamp, and look for a similar quality / age / price solid state pair, I wonder if I would get a better performer? But then again, the ARC tube gear does sound excellent...

Mark

John, Is the adjustibility of gain is the LS25 applied after the source but before the volume control and line stage amplification (tubes).  It did on my ARC Pre (a different model). The blurb I read on this pre-amp talked about the ability to reduce source gain in the context of matching gain of multiple sources. I didn't see anything about reducing pre-amp output gain. Typically you can only change pre-amp output gain either by internal implementation of a resistor or by adding an aftermarket fixed attenuator.

 If so, then any tube noise (or any other noise for that matter) would be passed on to the amp full strength. Since Mark's noise increases as he rotates his volume attenuator, the cause of the noise  increase must originate in the pre-amps circuitry before the amplification stage or in the source, which IMHO would more likely be the phono stage which are notoriously noisy. With a phono stage the noise could originate with the design itself, of if it uses tubes, then the tubes might not be low noise enough. It could also be the phono cartridge itself. 

Mark, I haven't read the preceding posts.  I'm sure Al or someone else have already mentioned this to you. But, I would point out that the difference between 100wts and 200 wts is only 3db, i.e. not very noticible. Now if your speakers require an amp with high(er) current (i.e. they have a impedence curve dropping to 4ohms or less) this could be an exception. But even if your amp could produce 800wts at  2 ohms you still would not be solving any noise issues caused by your pre-amp's amplifications stage.

FWIW. Forgive any redundancy created by existence of preceding posts.

Mark, your ARC LS25 is a  selectable gain line stage. It looks like you can set the gain anywhere between 0 dB and 18 dB. What do you currently have the LS25 gain set at?

The line stage gain will not make any difference. The volume control won't affect the noise of the line section. The only thing it can affect is how much noise is present from sources, like the phono section. Its my opinion that this is where the problem lies. It might simply be noisy tubes and it could also be that the phono cartridge has output slightly too low for the phono section to work with gracefully.

Do you think my Whest PS .30R is the culprit here?  I can definitely say that my PS Audio DAC does sound quieter than the analog, both driven through the ARC preamp.  I was under the impression that the Whest is quite a capable phono stage, with ample gain and balanced circuitry.  It is definitely a confusing process to determine how components play well together!